Metal drawing dog



(No Model.; Y l

- P.M.HAAS.

` METAL DRAWING DOG. yN. 293,166. Pfaaented Feb.' 5, Y1884.`

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-\ byI am enabled touse dogs having biting ends UNITED STATESA d PATENT Brice.

'PHILIP M. Haas, or YoUNGsTowN, eine, Assicnon or cnn-HALF To ANDREWS, Tinos. a co, or sAME rnacn.

METAL-DRAWING Doe.

.. SPECIFICATION forming part of LettersA PatentNo, 293,166, dated February 5, 1884.

Applieaiion filed April 20, 1883. (No model.)

To all whom it may concer-12,.-

Be it known that I, PHILIP ilInLANc'ri-ION IIAAs, a citizen of the United States, residing at Youngstown, in the county of Mahoning and State of Ohio, have invented new and useful Improvements in Metal Drawing Dogs, of which the following is a speciiication.

My invention is directed to the production of a dog or grasping deviceparticularly adapted for use in machines for drawing metal bars, shafts, or wire through a die for reducing,

straightening, and polishing `such articles.

The object of my improvement is to construct such a grasping device with dogs adapted to tighten their hold upon the article by reason of being coupled together at their gripping ends in such manner that they will be supported by such coupling, to cause them to bite with aforce upon the article increasing in proportionV to the resistance upon the article being drawn. rlhe dogs are coupled together across the line oi' their gripping endsV and at right angles to the line of draft, and

they operate in the arcs of circles, their outer ends being coupled to` a sliding draw-head, which also has an adjustable connection in the line of draft withthe couplings of the gripping ends of the dogs, in suchmanner as to form a stop to limit the `deflection of the dogs in their biting action fronra right line, where.-

of single points and control the extent to which said dogs may bite into the article being drawn through the die. The construction by which this is effected gives a firm and safe grip upon the article and avoids the necessity of preparing the end of the article to receive I andform a hold for the dog.

The draw-head may be adaptedfor use in any metal-drawing machine, and I have thereforeonly shown in the drawings the grasping dev-ice in connection with a sliding draw -head and a portion of a bar representing the article grasped and being drawn through a gagingdie.

1 To more particularly describe my said invention, I will refer to the accompanying drawings, and specifically point out the partsand combinations which I claim asl new.

In these drawings, Figure 1 represents a vertical section taken through the central adjustable connection of the grasping device, showing the bar in gaging-die. Fig. 2 represents a top viewof the grasping device, the dogs being in the position they occupy when adjusted to receive the article to be gripped. Fig. 3 represents a similar view, showing the position of the dogs when gripped upon the article to the full extent to which their edges are permitted to bite into the article to give the required hold. view of the dogs and `their holders in their Fig. i represents va top relative positions when out of y action, detached from their coupling-connections. Fig. 5 is a view looking toward the inner side of the dogs and their holders. Fig. 6 is a front view oi' the dogs and their couplingconnections.

rllhe draw-head c maybe of any suitable conc c, coupled at their inner ends by plates cl 02,

crossing the line of draft, and pivoted to said dog-holders c on their upper and on their lower sides, between which coupling-plates the article passes in position to be gripped by the dogs. The dogs are confined to their pivoted holders by straps d d, which form keepers, within which, when set, they are clamped by screws e e, while a set-screw, f, tapped into a right-angled projection, g, on the outer end of the dog-,holder c, abuts against the outer end of the dog, so as to set it out from theholder to suit the size of the bar and supporti-he dog under the gripping action. vThe dog-holders, being pivoted attheir` ends near tothe grip- 'ping-points, are also pivoted at their outer ends to coupling-arms' h, which are alsoi pivoted to the draw-head. The dog-h olders c therefore are free to turn at either end upon their couplings. Now, the dog-holders being thus coupled, and the article to be gripped being placed between them, the dogs are brought aga-inst it by slighti e' seance ly moving their inner coupled ends outward or away from the draw-head. This movement of thel dogs may be effected by any suitable means, as it is only intended to set the dogs upon the article at the beginning ofthe operation of the drawing. I do this, however, by a device which also serves the purpose of limiting the extent to which the dogs are allowed to bite into the article. This device consists of a yoke, fi, which is divided or forked, so as to lap over the upper and under the lower coupling-plates, c2, and over their outer edges by lapping lips t2, and is secured to said coupling-plates by cap-screwsj in the line of draft, whereby the said yoke and coupling-plates are rigidly connected. This coupling-yoke terminates in ascrew-shank, 7c, which passes through an opening in a boss or projection, Z, on the top of the draw-head, and is provided with jam-nuts m, which, whenA set, limit the outward movement of the yoke by coming against the draw-head projection Z, as shown in Fig. 3, so that `the jam-nuts m form a stop, against which the draw-head a pulls, and by which the dogs b are stopped from biting beyond a sufficient hold into the article. The arms 7i h are forked or slotted to receive the outer ends `of the dog-carriers@ c, and they are pivoted so as to have a certain play within the draw-head, as shownv in Fig. 2. The inner'- ends of the dog-holders c are pivoted to the coupling-'plates c2 and to the dog-keepers bypivots m, while the pivots a connect the dog-holders with the coupling-arms h. The dogs b are set upon the bar in commencing` the operation by means of a lever, a', pivoted to the projectionl ofthe draw-head, and connected to the yoke 't' by a pin or screw, s, passing through a slot, t, in the draw-head. The lever stands at right angles to the line of draft, and by moving it toward the grasping device the yoke i will be moved out from the drawhead, carrying with it the coupling-plates c2 and the biting ends of the dogs, which will.

thereby be drawn together upon the barand c grip it. The bar, however, is previously put through a gaging-die, a, and through a iixed abutment, '0, against which the die is supported, so that the end of the bar projects sufficiently beyond the abutment to be grasped by the drawing device. Power being applied to the'draw-head, the coupling-arms h draw upon the outer ends of the dog-holders, and' thus the dogs to approach the bar.

increase the biting action of the dogs upon the bar, because, the dog being arranged upon the inner sides of their holders, the latter will iiex 'on' the pivots ai a in such manner as to cause They are, however, only permitted 'tohave a limited movement toward the bar, and hence to bite into it only to a certain extent. This is effected by limiting the outward movement ofthe yoke by means ofthe jam-nuts m coming against 'the' draw-head and forming a stop, against which the yoke -pulls to hold the dogs'firm, while the force of the draft is exerted upon the rod in the line of the dogs by the coupling-arms 71,. In this action it is important to notice that the pivots m a of the dog-holders stand in line at right angles to the line-of draft, and that the biting-points are between such line of the pivots and the draw-head, and that in increasing the force of the dog-holdersthey describe an arc concentric with the pivots m of the coupling-plates.

Any suitable mechanism may be employed for operating the drawi11g-abutment. That shown consists of a chain, N, preferably passed through a semicireular way in the draw-head and connected to a drum or druins suitably supported at the end of the bed or frame upon which the draw-head slides. As shown, the draw-head is adapted to slide upon a troughshaped bedway, C, to which it is connected by side grooves or in any suitable way.

In another application I have shown this draw-head in a metal-drawin g machine having appliances for both drawing and pushing metal bars or shafts, in connection with Xed abutments and a removable gaging-die, in which the latter is first placed upon the bar, which t is then drawn through said die, and it is particularly to such machine that my improved drawing-(logis applicable. This patent, however, is only intended to cover the improvement in the drawing device, which may be used in any suitable metal-drawing machine.

I claim- 1. The combination, with a suitable drawing-die, .of `grasping-dogs, suitable holders therefor, pivoted couplingsfor the inner ends of said holders, and ,pivoted operating-connections for their outer ends, connected tothe draw-head, whereby the dogs are ada'pted to operate upon the article being drawn by a compound movement of their biting-points toward each other at right angles to the line of IOO draft, and by a deflection from a right line in their biting action in a direction opposite to that of the draft, substantially as described, for the purpose specified.

IIO

2. In a metal-drawing machine, the grasping and drawing device, consisting ofthe dogs 'b b, their pivoted holders 'c c, their couplingplates c2, their coupling-arms lz, the yoke z', provided with the nuts mf, the draw-head a, and the screws ef, for adjusting and supporting the dogs, substantially as described.

3. The combination, with a suitable drawing-die, of the dogs b I), their holders c c, the coupling-plates c2, to which said holders are pivoted across the line of draft, the pivoted coupling-arms hh, the draw-head, and means, substantially such as described, connected with the draw-head and with the couplingplates, whereby the biting action of the'dogs into the article being drawn is automatically limited.

4. The combination, in a metal-drawing machine, a suitable drawing-die, the draw-head a, the dogs b b, their pivoted holders d d c c, the coupling-plates e202, the coupling-arms h IO `which sai d operating-connections are also pivi, 7L, the adjustable yoke z', and the lever 7*, oonoted, substantially as described, for the purpose specified.

In testimony Wh ereof I have hereunto set my hand in the presence of two subscribing Witneeted therewith and with the draw-head, substantially as described, for the purpose speci-4 fied.

5. The dogs b I), their holders, and suitable nesses. pivoted eouplinoreonneetions for their inner A l ends, in Colnbintion with suitable operating- Y l HILH) M' HAAS' connections pivoted to the outer ends of said l Vtnesses:

A. E. H. JOHNSON,

dog-holders, and a suitable draw-head, to I J. XV. HAMILTON JOHNSON. 

